Researchers at the University of Vienna were interested in studying prosociality and dogs because of their high level of sociability and the presence of cooperative behaviors in puppy rearing, joint territorial defense, and group hunting. Also, since domestic dogs have been selected for social skills, that could also make them more likely to show pro-social behaviors.

In this study, dogs had the choice to pull one of two levers. One delivered a tray of food to a second dog and the other delivered an empty tray. The experiment was run with both strange and familiar pups (from the same household). As a control, the researchers also performed the test where the the receiver dogs were too far away to actually access the food or the receiver enclosure was empty.

The scientists found that the dogs were more likely to pull the lever for the food tray when they were paired with a familiar receiver. The dogs pulled the lever less when the receivers were too far away to access the food and they hardly ever pulled the empty tray.

According to lead researcher Friederike Ranger, this prosociality between dogs has never been experimentally demonstrated before. The team was most interested in how the degree of familiarity among the dogs influenced the behavior.

I'm curious to know how my dogs would respond to this experiment. If it were a decision between giving a treat or getting a treat, I know they would be much more selfish! What do you think your pups would do?

But it turns out that these ornaments are potentially dangerous, a lesson that a Pennsylvania family learned the hard way. Earlier this month the Pospisil family's dog, Lexi, snuck downstairs before everyone was awake and ate one of the salt dough ornaments on the Christmas tree. The couple had made them earlier in the season with their daughter, Alice.

The two year old pup was okay at first, but later started shaking uncontrollably and foaming at the mouth. The Pospisils immediately brought Lexi to the veterinarian, but it was too late. The high salt content of the ornament caused irreversible neurological damage and raised Lexi's body temperature to a dangerous 107 degrees. The poor pup had to be euthanized.

Heartbroken, the Pospisils took to Facebook to share their story and warn others about the danger of salt dough ornaments. So far their post has been shared over 80,000 times.

Some of my salt dough ornaments are well over 20 years old and are quite sentimental. Fortunately, we keep our Christmas tree behind an exercise pen, safe from the dogs and cat. However, I did move the salt dough ornaments to spots high up on the tree just in case. And for future crafts, I plan on switching to a clay recipe without salt.

Do you have salt dough ornaments on your tree?

Dogs lap water because they have incomplete cheeks and can't create the suction we use to drink liquids. This means that they have to use their tongues to raise water upwards. But they aren't the only animals that need to do this. Cats also have incomplete cheeks, but are much neater when they drink.

To explore this mystery, the researchers used photography and laboratory simulations with 19 dogs. They showed that the pups plunge their tongues into the water and curl them down towards their lower jaws. Then they quickly retract them, forming a column of water up towards their mouths, while creating a ladle with their tongue. The dog bites down at precisely the right moment to swallow, then immediately repeats the process.

In comparison, cats lightly touch the surface of the water without fully immersing it. The messiness of the dogs' style comes from the backward curl of the tongue, which increases the size of the water column, enabling dogs to drink more per lap than with a straight tongue.

While measuring tongue motion, recording water volumes, and observing lapping techniques, the researchers ended up creating a physical model of the tongue's interaction with the air-fluid interface, giving the team a tangible way to explore the method, and finally ending the mystery of why dogs are such messy drinkers.

As part of the study, researchers transferred nineteen embryos to the host female dog, who later gave birth to seven healthy puppies, two from a Beagle mother and a Cocker Spaniel father, and five from two Beagle couples. For successful in vitro fertilization, researchers must fertilize a mature egg with a sperm in a lab, to produce an embryo. Then they have to return the embryo to a host female at the right time in her reproductive cycle, which only occurs once or twice a year.

The researchers encountered numerous challenges along the way, such as getting the timing right for collecting the mature eggs, simulating what the female tract does naturally to prepare sperm for fertilization, and properly freezing the embryos. They eventually achieved success with fertilization rates of 80 to 90 percent.

According to Cornell professor, Alex Travis, scientists have been trying to do in vitro fertilization in a dog since the mid-1970s, but all attempts have been unsuccessful. They hope that this study will lead to advances in conserving the genetics of endangered species, using in vitro to introduce certain genes back into the gene pool of captive populations, and even preserving rare breeds of show and working dogs. 

It will be interesting to see what developments come from this work, and the ethical implications. While in vitro is used by zoos and conservation organizations to increase birth rates in captive animals, it's not exactly clear how it can be used to conserve the genetics of endangered species in their natural habitat. It sounds great that this technique could be used to preserve rare dog breeds, but it also has the potential to be abused. This also raises a larger ethical question of how the "host dog" is chosen and used. If a breeder repeatedly uses in vitro, could certain dogs become perpetual surrogates, similar to female breeding pups in puppy mills?

I'm happy to see that Cornell achieved this breakthrough, several decades in the making, but I hope that the dog world treads carefully as it navagtes how this technique is used.